I think some good reasons the 1911 is no longer as ubiquitous as it once was include: it's relatively expensive to make (and, correspondingly, pricier to buy), a lot of replacement parts require fitting, a bunch of people have been convinced that manual safeties are a bad idea for a carry gun, they are heavy (which is great for actual shooting and less-great for carry), they are generally capacity-constrained until you get to the really big double-stack variants that aren't carryable for most, most of them do need to be lubed to work well, the "controlled feed" design means there's less slop in the feeding process and more sensitivity to things being not-quite-right, etc.
None of those make them "irrelevant." None of those things have much, if anything, to do with actual performance, where a properly set-up 1911 really excels. There's a reason 1911s still get made and bought and used, and a reason other things get made and bought and used.